Is global warming antropogenic?

[Des]

I doubt it, can anybody back up their opinions with credible sources and/or reason's why they think global warming is, or isn't human caused?

I am interested in your opinions, that's why I am posting this topic.

Edit: 78 members and 558 guests and 213 spiders (whatever the hell those are) and 0 replies, thanks for the positive feedback, glad to know you show the least bit of interest in "your" earth.

 

[Andre]

Relax Des,

This place is not renowned for it's heated Anthropogenic Global Warming debates. They die out all the time.

My idea, the current warming is partly fiction due to the underestimated Urban Heat Island Effect, partly natural due to solar activity and enforcing natural cycles like the Pacific Decadal Cycle, the North Atlantic Occilation etc and partly anthropogenic with the main culprit probably soot and haze. Finally, on the very last spot there may be a very small signal due to increased CO2 levels. Not too much, due to saturation effects.

 

[Phobos]

Welcome to Physics Forums, Des. Check around the existing & older topics for many topics on Global Warming.

 

[Ivan Seeking]

We must act now on global warming

D/CE/7/2/4 (212/99) 22 December 1999

Sir/Madam

The release last week of data on global surface temperatures for the past
year by the US National Oceanic and Atmospheric Administration, The
Meteorological Office, and the World Meteorological Organisation, confirms
that our climate is now changing rapidly. These new observations, when
combined with our improving understanding of the climate system,
increasingly point to human influences as the cause of these climate
changes.

Temperature and other climatic indicators such as tree rings show that the
1990s have been the hottest decade of the last 1,000 years in the Northern
Hemisphere. The longest temperature record is from Central England, where
1999 is on course to be the warmest year since records began in 1659. For
the United States, 1999 will likely be the second warmest year on record
since 1880. Global land temperatures for 1999 appear to be the second
highest in history, while combined land and sea temperatures rank fifth.

The rapid rate of warming since 1976, approximately 0.2*C per decade, is
consistent with the projected rate of warming based on human-induced
effects. In fact, scientists now say that they cannot explain this unusual
warmth without including the effects of human-generated greenhouse gases and aerosols.

Articles in the US press imply that the global warming threat is being
oversold by citing particular examples of short-term natural changes. But
the overall pattern of recent short-term changes is in fact consistent with
scientists' projections of the impacts of global climate change. The
critical point is that we continue to see confirmation of the long-term
warming trend. Scientists on both sides of the Atlantic are carefully
looking at all of the evidence and using it to refine our understanding of
global climate.


The basic science of global warming has not changed since the topic was
raised earlier in this century. Furthermore, the consensus of opinion has
been growing, within both the scientific and the business communities. Our
new data and understanding now point to the critical situation we face: to
slow future change, we must start taking action soon. At the same time,
because of our past and ongoing activities, we must start to learn to live
with the likely consequences - more extreme weather, rising sea levels,
changing precipitation patterns, ecological and agricultural dislocations,
and the increased spread of human disease.

Our agencies are doing their part to provide the best possible data,
understanding, and forecasts for policy makers as they deal with these
difficult issues. Ignoring climate change will surely be the most costly of
all possible choices, for us and our children.



PETER D. EWINS
CEO
UK Meteorological Office

DR. JAMES BAKER
Under Secretary
US National Oceanic and Atmospheric Administration

http://www.solcomhouse.com/metnoaa.htm

Mountains of this stuff is available from NOAA and similar sources.

 

[Ivan Seeking]

Two of the nation's premier atmospheric scientists, after reviewing extensive research by their colleagues, say there is no longer any doubt that human activities are having measurable--and increasing--impacts on global climate. Their study cites atmospheric observations and multiple computer models to paint a detailed picture of climate changes likely to buffet Earth in coming decades, including rising temperatures and an increase in extreme weather events, such as flooding and drought. The study appeared December 5 in Science as part of the journal's "State of the Planet" series. The coauthors--Thomas Karl, director of NOAA's National Climatic Data Center, and Kevin Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research (NCAR)--conclude that industrial emissions have been the dominant influence on climate change for the past 50 years, overwhelming natural forces. The most important of these emissions is carbon dioxide, a greenhouse gas that traps solar radiation and warms the planet. "There is no doubt that the composition of the atmosphere is changing because of human activities, and today greenhouse gases are the largest human influence on global climate," they write. "The likely result is more frequent heat waves, droughts, extreme precipitation events, and related impacts, e.g., wildfires, heat stress, vegetation changes, and sea-level rise which will be regionally dependent." [continued]

http://globalchange.gov/